How did Xia Gui use monochrome ink in his paintings?

Xia Gui, a master of the Southern Song dynasty Imperial Painting Academy, utilized monochrome ink to create dramatic, atmospheric landscapes that emphasized space and distance. His approach to ink monochrome is characterized by several distinct techniques:12

• Tonal Range and Washes: Xia employed a sophisticated range of ink tones, transitioning from deep, rich blacks to subtle, evanescent washes of pale gray. These rich, wet ink washes were used to render mist and atmosphere, effectively hiding transitions and reducing fine-drawn detail to create a sense of depth and "limitless space".321
• Brushwork: He is noted for his use of "large ax-cut" strokes—broad, broken strokes derived from the technique of Li Tang—to render the rough, textured surfaces of rocks and mountains. These strokes, along with his use of a "split brush" and worn brush tips, allowed for a spontaneous, dramatic style that avoided the over-refined appearance of other academy painters.12
• Compositional Use of Void: In his Ma-Xia school compositions, Xia treated the "void"—the areas left bare or lightly tinted—as a positive element equal in importance to the solid masses. By juxtaposing these empty spaces with sharply focused foreground elements, he achieved a powerful sense of atmospheric perspective.12